Maternal exercise during pregnancy: Sex-specific impacts on offspring memory and maternal deprivation effects

Maternal deprivation (MD) is a well-established paradigm used to study the effects of early-life stress on offspring brain development and behavior, particularly memory. Maternal exercise (ME) during pregnancy has been shown to influence offspring brain development and behavior. Our study examined whether ME protocols—stop, start, reduce, or maintain running during pregnancy—could protect offspring from MD-induced memory deficits and impact hippocampal oxidative balance. Initially, adult Wistar female rats were divided into five groups: non-exercised mothers (NE), mothers who exercised only before pregnancy (PRE), mothers who exercised before and reduced the intensity during pregnancy (RED), mothers who exercised at the same intensity before and during pregnancy (EQUAL), and mothers who started exercise during pregnancy (GEST). After delivery, the groups were subdivided into control (CT) and MD. At 90 days of age, the offspring underwent an object recognition (OR) memory test, and hippocampal lipid peroxidation and catalase (CAT) levels were measured. MD-induced memory deficits in male but not female offspring. Only the male PRE group showed a memory deficit, while all other exercise protocols prevented the MD-induced deficits. MD did not affect hippocampal cell membrane peroxidation, and PRE and EQUAL protocols increased catalase levels compared to NE + CT controls. Our results highlight that maintaining or starting exercise during pregnancy mitigates memory deficits induced by MD, particularly in male offspring.